A catheter is a flexible tube with a diameter of approximately 2 mm and a length of approximately 1 m. The catheter can be inserted from a femoral artery and advanced to a target site such as the heart or the brain. When a contrast agent is supplied from the front end of the catheter, radiography can be performed.
A catheter through a hole of which a guide wire is passed has been known. When the catheter is inserted from a femoral region, first, the wire is first inserted in the femoral region, and then the catheter is sent out along the guide wire, whereby the catheter can be made to reach a target site.
For a thrombolytic treatment of heart and brain vessels, a catheter is inserted in the body, and a thrombolytic agent (urokinase) is released from a front-end portion thereof. Moreover, a thrombolytic treatment using a laser beam is also known. Since the laser beam is attenuated by blood vessels, several devices have been proposed.
In a thrombolytic treatment described in the following Patent Document 1, it has been described that attenuation of a laser beam can be suppressed by advancing a laser beam into a contrast agent while releasing the contrast agent from the front-end portion of a catheter, whereby a thrombus can be dissolved. It has been provided that the laser beam is emitted from a movable optical fiber through a hole provided in the catheter.
In a thrombolytic treatment described in the following Patent Document 2, it has been provided that a pulsed laser radiation is emitted from the front end of an optical fiber protruded from the front-end portion of a capillary tube to cause ultrasonic vibration, whereby a thrombus can be dissolved.    Patent Document 1: Japanese Patent Registration No. 322885    Patent Document 2: Japanese Translation of International Application (Kohyo) No. 2000-508938